An active matrix organic light emitting diode display panel attracts tremendous attentions and is becoming a mainstream display panel as its advantages such as being light, ultrathin and of a high contrast.
Referring to FIG. 1, a structural schematic view showing an organic light emitting diode (OLED) display panel in the related art, the OLED display panel includes: a base substrate 101, a buffer layer 102, an active layer 103, a gate insulating layer 104, a gate electrode 105, an interlayer insulating layer 106, a source/drain electrode 107, a passivation layer 108, a planarization layer 109, a first electrode 110, an organic light emitting layer 111, a second electrode 112, a pixel defining layer 113 and a glass packaging substrate 114.
In general, the OLED display panel in the related is of a low luminous efficiency, because that a light is totally reflected when entering an interface between the pixel defining layer 113 (being of a refractive index of about 1.8) and the glass packaging substrate 114 (being of a refractive index of about 1.5) and an interface between the glass packaging substrate 114 and an atmosphere (being of a refractive index of about 1) at an angle larger than the total reflection angle at the interface therebetween, as a result, about 20% in the total amount of emitting light emitting from the organic light emitting layer exits out and the rest light (about 80%) is restricted in the form of a guided wave inside the pixel defining layer 113 and the glass packaging substrate 114, which results in a decrease of the luminous efficiency.
Therefore, it is urgent to solve the technical problem to increase the luminous efficiency of the OLED display panel.